Thomas j



(No Model.) 7 y T. J. CAMPBELL.

WRENCH.

No. 322,256. Patented July 14, 1885.

@w E S S E N n W UNITED STATES PATENT OFFICE.

THOMAS J. CAMPBELL, OF VVESTFIELD, MASSACHUSETTS, ASSIGNOR OF ONE-HALF 1TO MOSES P. BRECKENRIDGE, OF SAME PLACE.

WRENCH.

SPECIFICATION forming part of Letters Patent No. 322,256. dated July 14, 1885. Application filed April 20, 1885. (No model.)

To all whom it may concern.-

Be it known that I, THOMAS J. CAMPBELL, a citizen of the United States, residing at Westfield, in the county of Hampden and State of Massachusetts, have invented new and useful Improvements in Wrenches, of which the following is a specification.

This invention relates to improvements in pipe-wrenches, the object being to provide a wrenchfor pipes and similar cylindrical objects of improved construction relative to simplicity and strength of parts and ease of manipulation, whereby it is more quickly adjusted to its work than are wrenches made as heretofore with screw devices for that purpose.

In the drawings forming part of this specification, Figure l is a perspective view of a pipe-wrench constructed according to my invention. Fig. 2 is a side view of the movable jaw thereof, a portion of the jaw-yoke, and the spring.

In the drawings, a is the bar of the wrench,

having the fixed 'serratedfaced jaw b at'its end, and having that side thereof adjoining the under side of head b provided with serrations z, one of whose faces is about at right angles to the length of the bar a and the other outwardly inclined. The bar is provided with the usual handle. The movable jaw c is provided with an inclined serrated end, 12, constituting the face of the movable jaw opposite the face of the fixed jaw 12. The side it of the movable jaw c,which engages and co-operates with said serrated side of the bar a, as hereinafter described, is curved, as shown, and provided with serrations corresponding with those above mentioned on the bar. By reason of the said curved form of the side h of the jaw c the normal contact position of the jaw cwith the bar a is that shown in Fig. 1that is to say, the contact-point of the jaw is about midway between the ends of the side h-and therefore said jaw is capable of an automatic rocking movement against the side of the bar, as and for the purpose hereinafter set forth; and,furthermore, the limited contact of the jaw with the bar renders it easy to move the jaw to any required position to or from the jaw I) to adjust the wrench to different sized objects. The jaw c is loosely attached to the bar a by a flat yoke, d, secured to the jaw and extending around the bar, but leaving space enough between the rear side of the bar and the opposite inner face of the yoke to permit the jaw to move freely in a line at right angles to the bar, clear of the latter, and to have the requisite unobstructed rocking motion on the side of the bar. A spring, 0, of flat metal is located between the rear side of the bar a and the yoke d for holding the jaw 0 against the bar and secure it against moving thereon when the wrench is not being used on pipe or other article, said spring not performing the office of holding the jaw and bar in engagement with each other when the jaw is under the great strain consequent upon the cam-action of the latter as its end 1) swings toward the bar when a pipe is being turned with the wrench, for under such circumstances the forced engagement of the serratiohs on the bar and on the curved side of the jaw serves to lock the bar and jaw together, and then the spring is under the control of the jaw, for it is deflected toward the bar in proportion to the inward swing of the jaw.

, To use the wrench, a pressure upon the end of the yoke 01 deflects spring 6 and moves jaw 0 out of engagement with the serrations z of the bar, thereby allowing jaw 0 to be moved to or from the fixed jaw 12, and when the inner end of the face '12 of jaw c is against the pipe to be turned the yoke is released and spring 6 draws the serrations of the jaw and the bar into engagement. The handle of the wrench being then moved in the usual direction for turning the pipe the curved side of jaw 0 rolls upon the side of bar a, the face 1: approaches the face of jaw b, and the pipe, being forcibly gripped between said two faces, is turned. By holding the jaw 0 against the side of bar auntil said pipe is fully gripped the spring may be dispensed with, and so with the yoke d,so far as the pipe-turning functions per se of the wrench are concerned. It does not aid in the latter, but serves as a means of attaching the jaw to the bar, so that it may always be i proper place for use when wanted. j

The jaw b and the bar a are of suitable metallic construction, and the jaw cis made preferably of steel.

By means of the construction above described-viz., the bar a, having serrations on its side, and the head I) combined with' the jaw 0, having the curved serrated side h-certhere is no further need of nut and screw detain pivoted features heretofore prevailing in Wrench construction whereby said cam-motion of the jaw is obtained are done away with,and

vices for setting the movable jaw to working position, and thus the cost of the wrench is greatly reduced while its working efiicieney is preserved.

WVhat I claim as my invention is- 1. In a wrench, the combination, with the bar a, having serrations z thereon, and the fixed head 1), of the movable jaw 0, having its side h curved and serrated to engage with said serrations on the bar and rock thereon, and a Witnesses:

WM. H. CI-IAPIN, Gno. TIIQWVARWIOK. 

